High Efficiency Classes of RF Amplifiers

Abstract

This article is dealing with high efficiency RF amplifiers in modern classes F, E and J.The first part is focused on basic function, main parameters and the output matching topologiesof the mentioned classes. Output voltage and current waveforms were simulated for each class ofhigh efficiency amplifiers. The primary focus of this work is the practical design of class F amplifierfor 435 MHz band with E-pHEMT transistor. Power added efficiency (PAE) of amplifier achieved58% and output power was 27 dBm with 14 dBm of input power. Amplifier was realized exclusivelywith lumped components in order to adhere to the given dimensions. Class F amplifiers designed atmegahertz frequencies and with E-pHEMT transistor are quite rare and this article could help designerswith understanding narrowband F-class amplifiers with higher efficiency. This amplifier can be usedin long range IoT application, because of its low consumption of energy which is necessary in thismodern technology. All results were simulated within ADS Keysight environment. Every simulationwas realized with nonlinear models from Modelithics.